CONOLAMPAS SIGSBEI. 49 
of the distance from the apex to the ambitus, forming the rudimentary 
petaloid ambulacra. At the extremity of these petals, the pores suddenly 
come close together, the poriferous zones becoming extremely narrow, and 
continue thus narrowed to the ambitus, and over to the actinal side, until 
they meet the floscelles. The anal system is covered by an outer row of 
three large plates and one smaller one, with a few smaller plates closing the 
outer edge of the anal system. 
It was with considerable hesitation that I referred this species, when first 
described, to the genus Conoclypus. While it undoubtedly agreed with it in 
having a central apical system, a high conical test, and the five ambulacra 
of the abactinal side equally developed, yet the arrangement of the pores 
(PI. XVII. Fig. 7) and the development of the phyllodes and of the bourrelets 
(PI. XVII. Fig. 5), the transversely elliptical anal system (PI. XVII. Fig. 6), 
and the structure of the apical system (PI. XVII. Fig. S), seemed to ally 
it more closely to Echinolampas. From the latter genus it differed, how- 
ever, in the arrangement of the petaloid ambulacra, which do not ibrm open 
petals as in the species of Echinolampas thus far known, but merely straight 
poriferous zones, not furrowed (PI. XVII. Fig. 2), extending close to the 
ambitus. This feature alone would pei'haps seem insufficient as a generic 
distinction, for we find in E. depressa of Gray that the ambulacral petals are 
modified somewhat from the characteristic Echinolampas type {E. oviformis), 
and besides not having closed petals, the poriferous zones of the different 
ambulacra are all of unequal length, somewhat as in E. Alca-andri De Lor. 
(see PI. XVI. Fig. 1), one of the characters by which Prof. F. J. Bell* 
attempted to separate the genus Palaaolampas from Echinolampas. De 
Loriol t is of opinion that the characters on which Mr. Bell attempts to 
establish the genus Palieolampas are insufficient, yet we may find it con- 
venient from the great variation we find in the petaloid areas of Echino- 
lampas to adopt Palseolampas as a subgeneric type.:}; 
Zittel was the first to show, in his Handbuch dcr Palivontologie (I. 515), 
that some species of the genus Conoclypus possessed teeth. This led De 
Loriol to make an examination of this genus, and he found that it really 
contained two generic types, one with ph3'llodes, which was edentate, and 
another in which there is no trace of phyllodes, but an enormous develop- 
ment of the bourrelets, which is provided with teeth. For the first type 
* Proc. Zool. Soc. London, 1880, p. 43. % See page 46. 
t Mem. de la Soc. de Phys. et d'Hist. Nat. de Genfeve, 1880, XXVII. 88. 
